Image processing system, image processing apparatus, aberration correction method, and computer-readable storage medium

Abstract

An image processing system, which corrects an aberration generated in an optical system by executing coordinate conversion of pixels of an image, has a table which holds correspondence between the positions of pixels before and after the coordinate conversion, acquires coordinates after conversion corresponding to the coordinates of representative points to be converted from the table, and calculates coordinates after conversion of a pixel between the acquired representative points by an interpolation calculation using a Lagrange interpolation formula.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to an image processing system, image processing apparatus, aberration correction method, and computer-readable storage medium, which correct aberrations of an optical system.[0003]2. Description of the Related Art[0004]In recent years, as a technique for seamlessly blending physical and virtual worlds in real time, a so-called MR (Mixed Reality) technique is known. As one MR technique, a technique using a video see-through HMD (Head Mounted Display; to be hereinafter abbreviated as an HMD) is known. With this technique, an object which nearly matches an object observed from the pupil position of an HMD user is captured using, for example, a video camera, and CG (Computer Graphics) is superimposed on that captured image. Then, the HMD user can observe an MR image.[0005]The video see-through HMD acquires digital image data of an object by capturing an image of that object using a charge coupl...

AI Technical Summary

Benefits of technology

[0022]The present invention provides a technique which can reduce coordinate conversion errors even when the size of a table used in coordinate conversion of pixels is reduced upon correction of image forming position deviations caused by aberrations.

Problems solved by technology

When an optical system is configured using inexpensive lenses or by suppressing the number of lenses, high image quality of an image to be displayed cannot often be maintained due to lens aberration.

That is, barrel- or pin-cushion-shaped images are often obtained due to distortion aberrations of lenses.

Also, red, blue, and green color bleeding appears at the boundaries of object images due to chromatic aberrations of magnification of lenses.

However, the size of a reference table which stores the correspondence with the coordinates after conversion depends on the size of an original image and the conversion precision, and the table size also becomes extreme in recent high-resolution and high-image quality trends.

If decimation is made to have an interval more than 16 pixels, errors at the time of interpolation increase.

However, the aforementioned related techniques suffer the following problems.

For this reason, it is expected to become increasingly difficult to reduce the table size while maintaining or improving the conversion precision.

This means that the bicubic interpolation is not suited to interpolating image forming position deviations, which change smoothly.

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